import java.util.Set;
import java.util.Iterator;
import java.util.HashSet;
import java.util.Random;
public class Test05 {
  public static void main(String[] args) {
    Set<Integer> set = new HashSet<Integer>();
    Random random = new Random();
    while(true){
        Integer a=random.nextInt(20)+1;
        set.add(a);
    if(set.size()==10){
        break;
      }
    }
    System.out.println(set);
  }
}